updating an example pipelinerun with array indexing

[pritidesai]

Changes

• Validate param values indexing into an array which are mapped to a pipeline params instead of echoing.
• Add an example of how to reference a single element from an array.

This is for the preparation of a potential promotion of #5688.

Signed-off-by: pritidesai pdesai@us.ibm.com

/kind misc

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Release Notes

NONE

[XinruZhang]

Thanks @pritidesai !

I gave it a try and figured out that the PipelineRun failed because its child TaskRun failed to substitue the environment variable 🤔 Not sure why does that happen.

TaskRun  "step-echo-params-1" exited with code 1 (image: "docker.io/library/bash@sha256:46aef8866a15877c36cf72736f1433e827c648d27dfcc9f1c1f187e8df762be9"); for logs run: kubectl -n default logs pipelinerun-param-array-indexing-c8jkb-deploy-pod -c step-echo-params-1

> kubectl -n default logs pipelinerun-param-array-indexing-c8jkb-deploy-pod -c step-echo-params-1

failed to validate the one and only argument of the script
Want: staging, Got: $(params.environments[0])

[XinruZhang]

It seems to be a bug, created an issue #6066 to track it.

[Yongxuanzhang]

staging

Could you check if you have enabled alpha feature flag? I can get the same error if not enabled.
The example should work.

[pritidesai]

Could you check if you have enabled alpha feature flag? I can get the same error if not enabled.

Thanks @XinruZhang and @Yongxuanzhang. Yeah its misleading, we could do a little better at handling this - I have created an issue -#6102 - addressing a similar behavior, using alpha feature without enabling alpha flag.

[XinruZhang]

/lgtm

[XinruZhang]

Thank you @pritidesai !

[Yongxuanzhang]

hope I can approve 😅

[jerop]

thank you @pritidesai!

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jerop, Yongxuanzhang

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